Thank you so much Jake!!
Could I get help with approaching this 5 mark question? I don't know how you can involve equations with polymerisation? I know it might be annoying to ask you to draw it but I was never taught this properly and it just came up in a practice paper and it's obviously worth a lot of marks so if you could maybe refer me to a website that shows it well that would be really awesome!
EDIT: I'm not sure what the difference between an oxidising agent is and something which oxidises. They're not the same but I don't know how to remember a good definition to not get confused. Any advice would be greatly appreciated
Hey,
The polymerisation reactions of these two reactions are something you need to know. There is a dotpoint about PVC and Polystyrene. I would recommend going through the HSC dot points, and figuring out if there's anything you've missed out on.
You need to be able to distinguish between addition polymerisation and condensation polymerisation. Addition polymerisation occurs when the monomers 'link' up without any elimination of a small molecule. Condensation polymerisation occurs when the monomers 'link' up and elimination a small molecule. The first one will look like this
You can tell that, since the monomer has a double bond, the bond will just 'split' open and react with other monomers.
The second one doesn't have a double bond, so a small molecule will be eliminated. One of the -OH groups will be eliminated from one side, and one -H from the -OH will be eliminated from the other side. This means that a product of the reaction will be water (H2O).
Additionally, you can talk about the standard initiation, propagation, termination steps required of polymerisation.
An oxidising agent is something that causes something else to oxidise. Thus, it reduces.
Molar heat of combustion has to do with how many bonds are broken. Thus, the more a molecule 'breaks down', the higher the molar heat of combustion. The bigger the molecule, the more it can combust into CO2 and H2O. So, the answer is D
Oxygen rarely changes oxidation state, so let's ignore it for now.
The initial charge of KMnO4 is zero. Thus,
The oxidation state of Manganese, initially, is +7. Looking at the right hand side
The final oxidation state of Manganese is +3. Therefore, it has decreased in oxidation number (gained electrons). The answer is B
Each step on the pH scale is a factor of 10. So, the Hydrogen ions in Milk 10 times more concentrated than in Distilled Water. The Hydrogen ions in Rain water is 10*10=100 times more concentrated than in Distilled water. the concentration in Wine is 10*10*10=1000 times more concentrated that in Distilled water. The answer is A.
The initial pH is going to be
We want the final pH to be five, so we need
Thus, initial concentration is 0.001 and final concentration is 0.00001.
So, we need to ADD 1980mL, as there is already 20mL and the total volume needs to be 2000mL